Speed control valve unit



T. T. TUTTLE SPEED CONTROL VALVE UNIT July 22, 1952 2 SHEETS-SEAT l Filed March 14, 1947 y 22, 1952 T. T. TUTTLE SPEED CONTROL VALVE UNIT 2 SHEETS-SHEET 2 Filed March 14, 1947 jl rve/rfor 1/0/70/7 Z. Ta ff/e Patented July 22, 1952 "SPEED CONTROL VALVE UNIT,

Tilmon T. Tuttle, Dayton, Ohio Application March 14, 1947, S eriaINo.734,614

This invention relates'to a speed control valve unit, and more particularl-yto such a unit as applicable to motor vehicles.

A primary objectof this invention is the provision of an improved valve unit for a-hydraulie-drive system adapted to reduce the loss of power between the engine 'and'the driving device forthe wheels of avehicle.

A further object of the invention is the provision of such a valve unit which accomplishes the foreg'oing objects by the elimination of the conventional clutch, transmission, universal, drive shaft, and differential;

A -fui-ther'objeet of the invention isthe provision of an improved speed control valve for the vehicle so arranged and constructed as to permit the engine-to run at a constant speed, and, by control of the quantity ofthe fluid admitted to' the drive motors-associated with the wheels oflavehicla-to control the speedthereof.

1 An additional object of the invention is the provision of a control valve unit for hydraulic drive systems which is sturdy and durable in c'onstruction,-= reliable and'cfficient in; operation, and relatively simple and inex ensive to manufa'cture, assemble'and-install;

Still other objects reside in the combinations of elements, arrangements of p'ar'ts, and features of'c'onstruction,all as: will be morefully pointed ou't-liereinafterand disclosed in the accompanying drawings, wherein there is shown a'pref'err'ed embodi mcnt of this inventive concept.

' In the' drawingsz- Figurel is a schematic top plan'view of a motorvehicle utilizing the valve unit-of the instant invention; the bodyand certain other parts thereof being omitted for thesake of' erally indicated at IO-theframe of a motor v'e hicle of any desired 'conventionaltype provided with--froht Wheels NH, rear wheels 12, and an engine l3 of any desired-conventional type.

The engine IQ is directly'and operatively con nected to a pump l d whichis supplied with hy-' d'raulicfiui'd from a reservoir I 5 through a main 2- Claims. ((31. 137-115) supply pipe" [6. A discharge pipe llleads from the pump to'a speed control valve. I8 to be'rnore fully described hereinafter. From the valve IB' a return line [9 leads to a filter 20, iron; which a pipe 2i returns fluid to the reservoir l-5.

The valve 18 isalso provided with an operating connection 22 that leads to a reverse valve 23- of the slide valve type. From the reverse" valve 2 3 an operating connection zdlea'ds a T 25 from which a pipe 26 leads through a T 27 to a transverse pipe '28, which in turn is connected, at its opposite ends, with hydraulic driving motors, 29 associated with the" rear Wheels [2; 7 v p The reverse valve 231s alsoqprovided with a reverse connection -3ll-whi'chextends through a T 3| to a pipe 32 connected by a T 33 with a transverse pipe 34, which alsocoinmunicates with the motor units" 29} for operativlyfdrivin'g' the motors in the reverse direction. The'inotor units 2 9 are also; provided with" return, drain, or seepage connections; 35 which connect a T 36, a P p 1,. a; r at, a: p pe 39'. and a T dflf tothe filter 20- and'fluid reservoir The T 40 also communicates with the returnline i9 and the T: 33 connected through a pipe 4i to the return sideof the va1ve2"3 The T fsZE and- M areconnectedthrough' pipes 4'5 and it, respectively, back tothe control valve unit l3. v

Means of conventional type are provided for directin'g'the' flow of fiuidiromthereverse valve 23' through either pipes-2'4 30 or 41, asmay be desired, and take the" form of a pivotally mounted lever 41 connected to" an operating rod 48'movable by a control lever 49* which extends intothe bodyof the vehicle at a point adja'-' cent the driver. The arrangementof this unit is conventiona l, and-may he of any desiredtype o'tvalve mechanism adapted for the-direction of fluid into one of the pipesi-nenticned for a p'ii'rpose to be more fully described hereinafter-. I

Means are also provided for controlling the valve unit 18 in-a ma nner tc be described in do: tail hereina ter, and inc-lode a rotatable rod ifl extending into the unit ra an'd connected-at its opposite end to an eccentric- 5 to which is? socure'd as 'by' n'ieans ofa pin 52-; an operating rod 53 wl-iich extends'to anaccelerator'pedal 54 su'itably mounted in the bod'yof} the vehicle The arrangement is such that movement 0; the accelerator pedal 54 tends through' 'theeccefitric 5'1 to'rotate meme to- 1 t o Referring now in -detail te thespeed control inlet pipe I1 from pump I4 communicates with a passage I1a, which in turn enters a bore 60 which communicates with a recess 6| within which is positioned a balanced spring-loaded valve 62, the loading being effected by springs 63 and 64 on opposite sides thereof. An outlet I9a communicates with recess 6| and has conlower extremity with a bracket 10, which carries a rotatable wheel 1|. The wheel 1| is adapted to abut an eccentric 12 carried by the shaft 50 which extends into a bore 13 in the unit I8; The

rod 50 is provided interiorly of the bore 13 with a cylindrical guidemember'14, and, adjacent the outer-extremity of the bore with sealing rings 15. A suitable fitting 16 secured to the exterior of the unit I8, as by screws 11, holds the parts in related assembly.

The valve member 61 has secured thereto a second valve 80 moving in a. recess 8| and provided with a spring-seating pin 82, surrounding which is one endof a coil spring 83, positioned in outlet passageway 22a which communicates with main outlet pipe 22. A r

The opposite end of the spring 83 seats against a threaded spring-retaining collar 85 suitably threaded within the passageway 22a and provided with a central aperture 86.

A bore 81 extends from the recess 8| to a transversebore 88 which inturn communicates with a bore 89 parallel to the: bore 81 which connects two parallel bores 45a and 46a, connected to .the

circulatory pipes; 45 and 46, respectively. A central artition between the passageways or bores 45a and 46a contains a bore 90 within which 'is positioned a spring 9| surrounding a spring guide rod and stop 92 adapted to be engaged by a pin 93carried by a valve member94. Member 94 is provided with a sealing ring 95 adapted to -prevent the passage of fluid into thebore90, and is connected, as by means of a reduced stem 96, to'a second valve member 91 provided with a sealing ring 98,'and a stop pin 99, the valve portion 91 being adapted to seat in the bore 88. It will be understood that fluid pressure in the passageway 81 will force the valve 91, and hence the valve 94, outwardly with respect to the passage 81 to close the, passageway 89, the movement of the parts being limited by the abutment of the pin 93 against the rod 92, and that such movement will effectively close the'passageway 89.

,Bores 81 and 89, respectively, are closed loy threaded caps I and |0I to seal the :ends

thereof, the bores being machined from the side wall of the unit I8. I

.A bore I02 extends from the main outlet22a outwardly through the wall of the member I8, its extremity being closed by a threaded cap 'I 03,

4 threaded cap I08 adapted threadedly to engage in the outer extremity of the recess 6|.

From the foregoing the operation of the mechanism should now be readily understandable. In operating the vehicle, the engine I3 may be started and adjusted to run at a desired R. P. M. at maximum efliciency. When it is desired to retain the vehicle in stationary position, the reverse valve 23 may be adjusted to neutral position, and the accelerator 5.4 released to adjust the parts to the position disclosed in Figure 2. Under these conditions, it will be seen that the pressure of fluid in the inlet I1a is suflicient to bias the valve 62 to open position, since the loading of'the spring 83 is in excess of that of the spring 63, and, the valve 61 being firmly seated against its seat 66, fluid from the pump I4 will pass through the inlet I1a, the bore 60, into the recess 6 I, and thence outwardly through the outlet I9a to pipe I9, returning through filter 2| to reservoir I5. Correspondingly, due to the absence of fluid pressure in the bore 81, the sprin 9I will bias the valve 94 to open position, in such manner that fluid from the driving motors 29 is permitted to circulate through pipes 45 and 46 into the passageways 45aand 46a, thus precluding blocking of the wheels and their associated motors 29, whereby coasting may be achieved.

When it is desired to apply power to the rear wheels I2 of the vehicle, pressure on the accelerator 54 will rotate the rod 50, which, through its eccentric 12, will open valve 61, the lower end of recess 65 being sealed by the valve 68, and admit fluid from the bore into the recess 8|, and'correspondingly, into the bore 81. Fluidpressure of the bore 81 will cause valve member 91 to move outwardly closing the bore 89 and precluding free circulation of fluid in the pipes 26, 38, 32, 34, 45 and 46-. Correspondingly, asthe valve 80 is moved out of the recess 8|, to open communica-.

tion therewith with main outlet 22a, fluid passes through the bores I 02 and I04 and the apertures I66 and, threaded cap member I08 into the bore 60 on the side containing the :spring 64, thus equalizing the pressure on opposite sides of the valve 62, and centering the same to close the outlet passage I9a. Under such conditions, and assuming that the reverse valve 23 is still in neutra1 position, the fluid circulates into the reverse mechanism 23 through the pipes 4| and 39, hence through T40 tothe filter 20 and back to the reservoir I5. Under suchconditions, it will be readily seen that a braking effect is applied to the rear wheels, since, by virtue of the closure of the bore 89, circulation of the fluid through the motors 29 is precluded, and the fluid exercises a material braking effect;

However, when it is desired to move the vehicle forwardly, the lever 49 is shifted in such manner as to close oif the pipe 4|, and permit fluid to pass outwardly through the pipe 24 to'the T 25, and thence through pipe 26 and T 21 to pipes 28 to energize the driving motors 29 which in turn rotate the wheels I2. After driving the motors 29, the fluid then returns through the return 35 and T 36, pipe 31 and T 38, through pipe 39 back to the filter 20, and thence to the reservoir I5.

Reverse driving movement is effected by moving the reverse valve in such manner as to close off the pipes 24 and 4| and pass fluidthrough the pipe 30 and T 3| to .pipe 32, and thence through T 33 to pipe, 34,, the fluid from which, entering the motors on the opposite side thereof causes a reverse rotation of the wheels I2. The

fluid under these conditions returns through the return 35 in the manner previously described to the reservoir 15.

It will now be seen that there is herein provided an improved valve control mechanismfor a fluid drive system which is extremely flexible in operation and of maximum efiiciency, the speed of the driving motors 29 being governed by the degree to which the valves 61 and 80 are opened, the speed of the engine remaining substantially constant at all times, which permits forward and backward movement of the vehicle at any desired rate of speed, which efiects the braking action when desired, and which further permits coasting or idling of the motor without changing the R. P. M. thereof.

It will also be seen that there is herein provided a device which accomplishes all the objects of this invention, and others, including many advantages of great ractical utility and commercial importance.

As various embodiments may be made of this inv'ntive concept, and as various modifications may be made in the embodiment hereinbefore shown and described, it is to be understood that all matter herein is to be interpreted merely as illustrative and not in a limiting sense.

I claim:

1. A valve device for use with fluid transmission for vehicles, comprising a body portion having a first chamber of uniform diameter, a second chamber having large and small chamber sections leading into each other, a first communicating bore leading into one end of the first chamber and into the small chamber section, a main inlet bore communicating with one end of the first chamber, a main outlet bore leading into the side of the first chamber, a main discharge bore leading into the large chamber section, a second communicating bore leading into the main discharge bore and the first chamber near its opposite end, a third chamber, a circulating bore having a part thereof leading into the third chamber, a third communicating bore connecting the large chamber section and the third chamber, a first plunger valve in the first chamber to cover and uncover the main outlet bore, spring means engaging the first plunger valve to cause the same to cover the main outlet bore when the pressure is balanced upon opposite ends of the plunger valve, a valve unit mounted within the second chamber and including a small valve for closing the small chamber section and a large valve between said first and second communicating bores for closing the large chamber section, a spring to seat the small valve and large valve of the valve unit and being stronger than the spring means, a second plunger valve mountto the opening of said small valve of said valve unit to close the circulating bore, a spring to unseat the second plunger valve, and manually operated means to operate the valve unit for unseating the small and large valves.

2. A valve device for use with fluid transmission for vehicles, comprising a body portion having a first chamber of uniform diameter, a second chamber having large and small chamber sections leading into each other, a first communicating bore leading into one end of the first chamber and into the small chamber section, a main inlet bore communicating with one end of the first chamber, a main outlet bore leading into the side of the first chamber, a main discharge bore leading into the large chamber section, a second communicating bore leading into the main discharge bore and the first chamber near its opposite end, a third chamber, a circulating bore having a part thereof leading into the third chamber, a third communicating bore connecting the large chamber section and the third chamber, a first plunger valve in the first chamber to cover and uncover the main outlet bore, spring means engaging the first plunger valve to cause the same to cover. the main outlet bore when the pressure is balanced upon opposite ends of the plunger valve, a valve unit mounted within the second chamber and including a small valve for closing the small chamber section and a large plunger valve between said first and second communicating bores for closing the large chamber section, the large plunger valve unseating after the small valve unseats, a spring to seat the small valveand large plunger valve of the valve unit and being stronger than the spring means, a second plunger valve mounted in the third chamber and movable in response to the opening of said small valve of said valve unit to close the circulating bore, a spring to unseat the second plunger valve, and manually operated means to operate the valve unit for unseating the small valve and large plunger valve.

TILMON T. TUTTLE.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS 

